Katma Tui was Green Lantern for the planet of Korugar during her tenure as a member of the Green Lantern Corps (this was in sector 1417). She replaced Sinestro as the Green Lantern for this sector. He had used his power ring to establish himself as totalitarian ruler of his planet. Katma Tui eventually helped lead the revolt against him which would result in his removal as planetary leader, of him being removed as a member of the corps and of being imprisoned in the anti-matter universe on the planet of Qward. She was nominated by Tomar-Re as the replacement Green Lantern for the sector, which she accepted. Despite this she was regarded as a villain by her native Korugarans as the Green Lanterns were falsely considered a symbol of tyranny because of the actions of Sinestro. She is therefore known as “Katma Tui the lost.”
Inherited Sinestro's Green Lantern ring after he turned evil (Sector 1417).

Katma Tui was model and member of Green Lantern Brigades at Sinestro's service. Afterwards she become Green Lantern for the planet of Korugar during her tenure as a member of the Green Lantern Corps (this was in sector 1417). She replaced Sinestro as the Green Lantern for this sector. He had used his power ring to establish himself as totalitarian ruler of his planet. Katma Tui eventually helped lead the revolt against him which would result in his removal as planetary leader, of him being removed as a member of the corps and of being imprisoned in the anti-matter universe on the planet of Qward. She was nominated by Tomar-Re as the replacement Green Lantern for the sector, which she accepted. Despite this she was regarded as a villain by her native Korugarans as the Green Lanterns were falsely considered a symbol of tyranny because of the actions of Sinestro. She is therefore known as “Katma Tui the lost.”
Inherited Sinestro's Green Lantern ring after he turned evil (Sector 1417).

Hand-to-hand combatant
Natural leader
Katma Tui wields a Green Lantern Power ring, which gives her several very formidable abilities and tactical resources:
Emotional Spectrum Green Will Energy Conduit: The rings use pure energy supplied by a Power Battery, which in most cases takes the form of bright green light. This energy is the green light of willpower of the Emotional Electromagnetic Spectrum. A Green Lantern's ring, considered by some to be one of the most powerful weapons in the known universe, has the ability to affect and use fundamental forces of the known universe, including electromagnetic energies such as gravity, radiation, heat, light, and powerful blasts of concussive force. It is also theorized that the ring also has a basis in other dimensional energies commonly called magic by users of such energies. The ring can also create fields of force formed from an unknown energy that is bound by the users' will. The limitations of such use are the skill, knowledge and imagination of the user.
Energy Projection: The ring can be used to fire blasts of energy or create weapons such as projectiles of them. The ring can project beams of force powered by the will of the user. Their appearance does not indicate the power of the weapon. The weapon's power is more an indication of the will of the user.
Force Field: The ring can create various force fields of various sizes and shapes to protect the wearer and others in the vicinity. With the cosmic scope of a Green Lantern's duties, it is only natural that the power ring is designed for operation in space. The ring creates a force field around the wearer, protecting them from the hazards of the void including filtration of stellar radiation and microscopic particulate matter which would ordinarily be fatal should the space debris strike the ring wielder at high speeds. An atmosphere appropriate to the ring wielder's biology is created inside the force-field while body temperature is maintained and waste products are removed. Gravitational stresses which could cause injury are stabilized for the ring wielder. Theoretically, a ring wielder could use the ring as their sole source of life support. The force field is created instantaneously whenever needed as part of the ring's automatic defensive system.
Energy Constructs: The primary function of the power ring is to provide a weapon capable of transforming the wearer's thoughts into physical constructs through the wearer's strength of willpower. A Green Lantern can create any particular items or construct that they can imagine as long as they have the willpower necessary to will it into existence. The constructs exist only as long as a Green Lantern is fueling them with their willpower. Items created by the rings are not indestructible and are only as powerful as the willpower of the Green Lantern creating them. The types of constructs usually reflects the ring wearer's personality.
Phasing: The power ring allows the wearer to pass through solid objects such as walls, though this is also a function of the ring-bearer's will and not an automatic ability of the ring itself.
Environmental Playback: Upon request, the power ring can recreate a holographic environment based on data in its memory banks. The ring-bearer can observe events in a ghost-like state, but the cannot alter the outcome of the playback. All objects in the playback will appear in the full spectrum of colors, regardless of the wielder's level of expertise creating simulacra. The power ring will automatically end the playback if outside interference warrants the ring-bearer's undivided attention.
Invisibility and Light Refraction: A ring-bearer can render themselves invisible by willing the ring to bend light waves around their body. A similar action allows an experienced ring-bearer to create objects of colors other than green, even simulacrums of living people.
Energy Absorption: The ring can absorb and store other energies. Doing so does not replenish the normal store of energy the ring has. For example: a ring that needs recharging but contained a store of electricity could only discharge that electricity.
Superhuman Strength: While not super strength of the conventional sense, a Lantern, while using constructs created by the ring, becomes capable of lifting/moving tremendous weights far heavier than they would normally be able to with comparatively little effort.
Flight: By the manipulation of anti-gravitons and directed molecular movement, the ring allows the user to fly at incredible speeds. In atmosphere, a Green Lantern has been known to fly as fast as Mach 10 in atmosphere by creating an aerodynamic envelope around their body. In space, a Green Lantern's flying ability has been shown to reach velocities far exceeding light speed. In atmospheres, air friction is not a hindrance since heat is either absorbed or reflected by the ring's field.
Wormholes and Spacial Warps: The power ring grants its bearer access to wormholes in space, enabling a Green Lantern to rapidly cut the time and distance needed to respond to an emergency. Black holes can also be navigated by experienced ring wielders. A Green Lantern can travel through a black hole to be deposited outside a white hole in a far off sector of space.
Time Travel: Time travel is possible with the power ring, though the further forward in time a ring-bearer travels, the more willpower it takes.
Limited Cellular Regeneration: A Green Lantern can use their ring to heal physical injuries in their self or others.
Electromagnetic Scanning: The ring has a wide range of detection abilities based on the imagination of the user. If the ring-bearer can conceive of it, they can probably detect it. Most normal electromagnetic phenomena are within the range of the ring, including radio, radar, television, infrared, ultraviolet, microwave, and high frequency band communications.
Thought Relay: Otherwise known as a telepathic link, which can be used to coordinate tactics with other Green Lanterns or report of the status of an active mission to a sector partner or other Lantern. The links can also be established with non-Green Lanterns, though it requires more willpower.
Galactic Encyclopedia: The earlier rings worn by the Corps functioned as references for their bearers. Having the vast knowledge of the Book of Oa to draw upon, each ring functions as a ready reference on most peoples, stellar events and conditions that may have been seen by other rings or other Green Lanterns.
Universal Translator: The power ring can translate virtually any language in the universe, facilitating diplomatic encounters rather than violent confrontations. Complications arise when a frame of reference for translation is not available, as evidenced during Katma Tui's induction of Rot Lop Fan into the Green Lantern Corps. Katma Tui had the difficult assignment of explaining the concepts of "light" and "color" to the sightless Rot Lop Fan. She overcame this barrier by using sound rather than light as the basis of the ring's power. Some Green Lanterns, such as the planet form known as Mogo, have used the ring to create an intermediary "being" to expedite communication.
Material Alteration: The Green Lantern's uniform is not made out of fabric. It is created by the power ring whenever the ring-bearer wills to wear it. Most Green Lanterns wear similar uniforms that are programmed into the ring by default. However, each Green Lantern is able to adjust their uniform to fit their own needs, personalities, or whims. The green parts of the wearer's uniform are usually very warm or hot to those who touch it, while the black parts are very cold. The uniform also produces a "siren" taking on the form of the Green Lantern Corps' symbol, circling the Green Lantern when active. The symbol, or badge, will not appear on the uniform until after a newly inducted Lantern has completed training on Oa, leading to the term "White-Circle" to describe a rookie Lantern.
Ring Duplication: A power ring is capable of duplicating themselves. Each duplicate shares the qualities and capabilities of the original ring. The duplicate rings are subject to over-ride control by the original ring-bearer, and take a significant expenditure of energy to create.
Emergency Beacon: A Green Lantern in distress can use their power ring as an emergency beacon. The alert can be directed to a Green Lantern's neighboring sector, or it can be a Corps-wide alert.
Homing Beacon: A homing beacon in the power ring can lead one Green Lantern to another. Though a power ring can be ordered to disguise itself to elude power ring wielding trackers.
Mind Alteration: Though the ethics of mind tampering may be debatable, sometimes it is deemed necessary. As the power ring relies on thought and will to operate, mind tampering is not impossible. The real difficulty lies in properly applying the power. There lies a risk of severe damage to the mind where alterations are being attempted should mistakes be made. A ring-bearer can use the power ring to erase portions of an individual's memories. Green Lanterns have used mind techniques as part of training. New recruits may be subjected to mind scans by other Green Lanterns or the Guardians of the Universe. They are taught to build mental defenses to protect themselves from mental attack. The power ring can also be used to beam information from the ring wielder to another being. Green Lanterns have used this technique to share information regarding their enemies during combat situations.
Pocket Dimension: A ring-bearer can use their ring to create a small extra-dimensional holding space in which they can store their power battery for ease of retrieval. These pocket dimensions can be accessed from any location.
Security Protocol: The rings can be programmed. They are coded to the wearer to make them unusable if stolen. The ring will refuse to take an action that would kill a being unless they are on Oa or have obtained permission. The Guardians recently removed the lethal force prohibition, first to allow lethal force against members of the Sinestro Corps, then against all enemies of the Green Lantern Corps.
Preset Conditions: Commands can be stored in the ring to be executed at a later date even if the bearer is not wearing the ring.

Katma Tui was Green Lantern for the planet of Korugar during her tenure as a member of the Green Lantern Corps (this was in sector 1417). She replaced Sinestro as the Green Lantern for this sector. He had used his power ring to establish himself as totalitarian ruler of his planet. Katma Tui eventually helped lead the revolt against him which would result in his removal as planetary leader, of him being removed as a member of the corps and of being imprisoned in the anti-matter universe on the planet of Qward. She was nominated by Tomar-Re as the replacement Green Lantern for the sector, which she accepted. Despite this she was regarded as a villain by her native Korugarans as the Green Lanterns were falsely considered a symbol of tyranny because of the actions of Sinestro. She is therefore known as “Katma Tui the lost.”
Inherited Sinestro's Green Lantern ring after he turned evil (Sector 1417).